A lot of people like switching caps and control. In fact I did the same for about a year before someone pointed out to me that it makes more sense to use the thumb for Control.
I also researched this topic a bit. Here's the keyboard that inspired Control, imho, to become the most used modifier:

The venerable LISP machine keyboard, the Space Cadet.
I found that using Caps as Control was a huge improvement, but my pinky got tired. Moving it next to the spacebar improved my finger fatigue tremondously. It takes a little getting used to, but after that it just feels so much better using my big fat thumb for this most used of all modifiers. In fact, I don't really get why the HHKB puts control at caps (I think it's been badly inspired by the Sun keyboards).
So the bottom row of my keyboard looks like this now:
CONTROL ALT CONTROL SPACEBAR CONTROL ALT CONTROLI leave the original control for other people that use the kb.
Mac keyboards are similar as well... Command is right next to the spacebar. I think this is a good design.